Time-resolved photoluminescence of the size-controlled ZnO nanorods

Size dependence of the time-resolved photoluminescence (TRPL) has been investigated for the ZnO nanorods fabricated by catalyst-free metalorganic chemical vapor deposition. The nanorods have a diameter of 35 nm and lengths in the range of 150 nm to 1.1 mum. The TRPL decay rate decreases monotonically as the length of the nanorods increases in the range of 150 to 600 nm. Decrease of the radiative decay rate of the exciton-polariton has been invoked to account for the results. (C) 2003 American Institute of Physics.X11100sciescopu

Epileptic spasms in paediatric post‐traumatic epilepsy at a tertiary referral centre

Aim. To recognize epileptic spasms (ES) as a seizure type after traumatic brain injury (TBI), accidental or non‐accidental, in infants and children. In the process, we aim to gain some insight into the mechanisms of epileptogenesis in ES.Methods. A retrospective electronic chart review was performed at the Children’s Hospital of Michigan from 2002 to 2012. Electronic charts of 321 patients were reviewed for evidence of post‐traumatic epilepsy. Various clinical variables were collected including age at TBI, mechanism of trauma, severity of brain injury, electroencephalography/neuroimaging data, and seizure semiology.Results. Six (12.8%) of the 47 patients diagnosed with post‐traumatic epilepsy (PTE) had ES. Epileptic spasms occurred between two months to two years after TBI. All patients with ES had multiple irritative zones, manifesting as multifocal epileptiform discharges, unilateral or bilateral. Cognitive delay and epileptic encephalopathy were seen in all six patients, five of whom were free of spasms after treatment with vigabatrin or adrenocorticotropic hormone.Conclusion. The risk of PTE is 47/321(14.6%) and the specific risk of ES after TBI is 6/321 (1.8%). The risk of ES appears to be high if the age at which severe TBI occurred was during infancy. Non‐accidental head trauma is a risk factor of epileptic spasms. While posttraumatic epilepsy (not ES) may start 10 years after the head injury, ES starts within two years, according to our small cohort. The pathophysiology of ES is unknown, however, our data support a combination of previously proposed models in which the primary dysfunction is a focal or diffuse cortical abnormality, coupled with its abnormal interaction with the subcortical structures and brainstem at a critical maturation stage.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/136710/1/epd2900.pd

Semiparametric Competing Risks Regression Under Interval Censoring Using the R Package intccr

Background and objective: Competing risk data are frequently interval-censored in real-world applications, that is, the exact event time is not precisely observed but is only known to lie between two time points such as clinic visits. This type of data requires special handling because the actual event times are unknown. To deal with this problem we have developed an easy-to-use open-source statistical software. Methods: An approach to perform semiparametric regression analysis of the cumulative incidence function with interval-censored competing risks data is the sieve maximum likelihood method based on B-splines. An important feature of this approach is that it does not impose restrictive parametric assumptions. Also, this methodology provides semiparametrically efficient estimates. Implementation of this methodology can be easily performed using our new R package intccr. Results: The R package intccr performs semiparametric regression analysis of the cumulative incidence function based on interval-censored competing risks data. It supports a large class of models including the proportional odds and the Fine-Gray proportional subdistribution hazards model as special cases. It also provides the estimated cumulative incidence functions for a particular combination of covariate values. The package also provides some data management functionality to handle data sets which are in a long format involving multiple lines of data per subject. Conclusions: The R package intccr provides a convenient and flexible software for the analysis of the cumulative incidence function based on interval-censored competing risks data

A key to room-temperature ferromagnetism in Fe-doped ZnO: Cu

Successful synthesis of room-temperature ferromagnetic semiconductors, Zn$_{1-x}$Fe$_{x}$O, is reported. The essential ingredient in achieving room-temperature ferromagnetism in bulk Zn$_{1-x}$Fe$_{x}$O was found to be additional Cu doping. A transition temperature as high as 550 K was obtained in Zn$_{0.94}$Fe$_{0.05}$Cu$_{0.01}$O; the saturation magnetization at room temperature reached a value of $0.75 \mu_{\rm B}$ per Fe. Large magnetoresistance was also observed below $100$K.Comment: 11 pages, 4 figures; to appear in Appl. Phys. Let

Semiparametric regression on cumulative incidence function with interval-censored competing risks data and missing event types

Competing risk data are frequently interval-censored, that is, the exact event time is not observed but only known to lie between two examination time points such as clinic visits. In addition to interval censoring, another common complication is that the event type is missing for some study participants. In this article, we propose an augmented inverse probability weighted sieve maximum likelihood estimator for the analysis of interval-censored competing risk data in the presence of missing event types. The estimator imposes weaker than usual missing at random assumptions by allowing for the inclusion of auxiliary variables that are potentially associated with the probability of missingness. The proposed estimator is shown to be doubly robust, in the sense that it is consistent even if either the model for the probability of missingness or the model for the probability of the event type is misspecified. Extensive Monte Carlo simulation studies show good performance of the proposed method even under a large amount of missing event types. The method is illustrated using data from an HIV cohort study in sub-Saharan Africa, where a significant portion of events types is missing. The proposed method can be readily implemented using the new function ciregic_aipw in the R package intccr

Warm needle acupuncture for osteoarthritis: A systematic review and meta-analysis.

Warm needle acupuncture (WA) is considered a potential intervention in the treatment of osteoarthritis (OA). To systematically evaluate the clinical efficacy and safety of WA in the treatment of OA. Systematic review and meta-analysis METHODS: Fourteen databases were searched from their inception until May 2022. Randomized controlled trials (RCTs) of WA for treating OA were identified. Study selection and data extraction were performed by two independent reviewers. The Cochrane risk of bias tool and the Grading of Recommendations Assessment, Development and Evaluation program were used to assess all included RCTs. A total of 66 RCTs met the inclusion criteria for this review. Most of the included studies had an unclear risk of bias, and the certainty of the evidence was very low. Twenty-four RCTs compared the effects of WA with those of oral drug therapies. Meta-analysis showed superior effects of WA for the total effective rate (risk ratio (RR): 1.22, 95% confidence interval (CI): 1.17 to 1.27, I  = 26%, p < 0.001, 24 studies, n = 2278), pain, and function. Eight RCTs compared the effects of WA+drug therapy, and meta-analysis showed favorable effects for the total effective rate (RR: 1.27, 95% CI: 1.18 to 1.35, I =0%, p < 0.001, 8 studies, n = 646). Eight RCTs compared the effects of WA and intra-articular sodium hyaluronate (IASH) injection on OA and found equivalent effects of WA on the symptoms of OA. Twenty-eight RCTs compared the effects of WA+IASH injection with those of IASH injection, and meta-analysis showed superior effects of WA+IASH in terms of the total effective rate (RR: 1.15, 95% CI: 1.11 to 1.19, I =27.3%, p < 0.001, 25 studies, n = 2208), pain, and function. None of the RCTs reported serious adverse events. WA may have some distinct advantages in the treatment of OA. However, well-designed RCTs with larger sample sizes are needed. [Abstract copyright: Copyright © 2022 The Author(s). Published by Elsevier GmbH.. All rights reserved.

Pattern Formation in a Two-Dimensional Array of Oscillators with Phase-Shifted Coupling

We investigate the dynamics of a two-dimensional array of oscillators with phase-shifted coupling. Each oscillator is allowed to interact with its neighbors within a finite radius. The system exhibits various patterns including squarelike pinwheels, (anti)spirals with phase-randomized cores, and antiferro patterns embedded in (anti)spirals. We consider the symmetry properties of the system to explain the observed behaviors, and estimate the wavelengths of the patterns by linear analysis. Finally, we point out the implications of our work for biological neural networks